This novel is primarily a work of fiction, but to an extent has been drawn from factual accounts recorded by those who actually witnessed the tortures and trials of the Middle Ages, and the period leading up to the end of the 17th Century. Both the wheel and the rack were common instruments of torture used extensively to extract confessions or instil terror in those insubordinate to both Church and State.
The use of hallucinogenic drugs was reputedly employed at witches' sabbaths and ceremonies throughout the Middle Ages. It has been suggested that many of the visions and revelations seen and recorded by those who experienced them in the 14th and 15th Centuries may have been inspired from the use of rotting grain in the baking of bread. The grain would be stored from a successful harvest and carried over in case of failure the following year. The fermenting grain produced a chemical not dissimilar to that used in the production of LSD, and it may not be too fanciful to suggest that the fantastic images conjured by mediaeval artists and described in this novel may have been drug induced.
Without doubt, learned men and women practicing medicine at that time were all too well aware of the enormous power that lay at their disposal, hence the importance played by the herbalist in the convent of Saint Dulcinea.
The rest is fiction.
Geoffrey Allen.